Why is the sky blue?

Answer 1

Dude. Do you know how many times this question has been asked before??

The scattering of electromagnetic radiation by particles with dimensions much smaller than the wavelength of the radiation, resulting in angular separation of colors and responsible for the reddish color of sunset and the blue of the sky.
But the sky is not blue, it only looks that way.

The sky is filed with very small molecules of water and when the light passes through the water it refracts and what you see is a blue haze. It gets darker the further up you look because it is backed less and less by refracted light and more by direct contrast of cloud matter and in the absence of clouds, space itself.

Answer 2

The sky is blue partly because air scatters short-wavelength light in preference to longer wavelengths. Where the sunlight is nearly tangent to the Earth's surface, the light's path through the atmosphere is so long that much of the blue and even yellow light is scattered out, leaving the sun rays and the clouds it illuminates red, at sunrise and sunset.

Scattering and absorption are major causes of the attenuation of radiation by the atmosphere. Scattering varies as a function of the ratio of the particle diameter to the wavelength of the radiation. When this ratio is less than about one-tenth, Rayleigh scattering occurs in which the scattering coefficient varies inversely as the fourth power of the wavelength. At larger values of the ratio of particle diameter to wavelength, the scattering varies in a complex fashion described, for spherical particles, by the Mie theory; at a ratio of the order of 10, the laws of geometric optics begin to apply.

Individual gas molecules are too small to scatter light effectively. However, in a gas, the molecules move more or less independently of each-other, unlike in liquids and solids where the density is determined the molecule's sizes. So the densities of gases, such as pure air, are subject to statistical fluctuations. Significant fluctuations are much more common on a small scale. It is mainly these density fluctuations on a small (tens of nanometers) scale that cause the sky to be blue.

Answer 3

Blue light is more energetic than other colors in the spectrum.

As light enters the atmosphere it gets scattered open striking molecules of gases in the air. The blue light does not scatter nearly as much as the other colors.
And as a result the sky appears blue, because the blue light takes a direct path to your eyes whereas the other colors are being scatted around.

Answer 4

the sky is BLUE because :

1. the atmosphere is principally made of nitrogen and oxygen gas ( 70% and 30 % respectively )

2. nitrogen and oxygen typically temporarily absorb all the colors of light ( the rainbow colors ) and release them.

3. they however release them differently according to their wavelengths ( e.g. colors ).

4. in particular, when the sun hits the atmosphere directly from above, the "blue" wavelengths of light get "scattered" to a much greater degree than the other colors.

5. this is a property of this particular wavelength ( blue ) when it interacts with nitrogen and oxygen.

6. the extra scattering of blue is what we percieve as a blue sky.

7. during sunrise and sunset, the angle at which the light hits the atmosphere causes it to travel thru a greater amount of the atmosphere and this causes bending or "refraction" of light.

8. during this time, the longer wavlengths ( e.g. reds and oranges ) get bent more and thus we see a "reddening" effect ( which is totally different from scattering ).

9. i have tried to explain this question without using too much physics so that everyone can benefit.

10. thanks and hope it answered your question :)

Answer 5

Actually, none of the answers so far are right. It is called Rayleigh scattering - the gas molecules in the air (not water droplets or dust particles) scatter shorter wavelength violet and blue light more than longer wavelengths.

It looks to us that the light is coming from the sky, but it is actually light from the sun that is scattered by those air molecules.

EDIT - sorry, there was a correct answer above that "snuck in" while I was answering!

Answer 6

The blue colour of the sky is attributed to Rayleigh scattering...the atmosphere scatters blue light (with minimum frequency)

Answer 7

the wavelengths of blue light are bounced off the ground and scattered at angles away from the ground, causing the particles in the sky to bounce back blue light to our eyes.

Answer 8

The sky is blue because the molecules in the air mostly reflect that color.

Answer 9

it is jsut the reflection of the oceans...an oceans looks blue because they also reflect the light from the sky

Answer 10

Because of light reflected off of earth's oceans.